Observation of Subsurface Crack of Carburized Steel (SCM415) under Single-Ball Rolling Contact Fatigue over 10~7 Cycles

摘要

Bearing fails due to the flaking failure which is caused by the subsurface cracks. The observation of the subsurface cracks is not easy beacause the cracks propagate inside the material. In order to observe the whole subsurface cracks, we performed rolling contact fatigue (RCF) tests of carburized SCM415 at over 10~7 cycles with the single-ball RCF machine. After the RCF tests, we directly observed the subsurface cracks.